Mixing and emulsifying apparatus



July 8, 1930. w, soN 1,770,302

MIXING AND EMULSIFYING APPARATUS Filed June 25, 1927 2 Sheets-Sheet l 70 I db f a 1 w [J J 50 on Z 2 July 8, 1930. A. w. EMP SON I MIXING AND EMULSIF'YING APPARATUS Filed June 25. 1927 2 Sheets-Sheet z-z lll Patented July 8, 1930- UNITED STATES ALFRED WALKER EMPSON, OF LONDON, ENGLAND MIXING AND EMULSIFYING APPARATUS Application filed .Tune 25, 1927, Serial No. 201,514, and in Great Britain June 26, .1926.

This invention relates to improved method of apparatus for the manufacture of compositionsof matter such as emulsions or the reconstitution of milk and cream from 3 their separated contents. The invention is also applicable for the manufacture of margarine, ice cream and so forth.

Generally, the method employed to produce emulsions and the like is to pass the mixture previously prepared through tortuous passages formed by juxtaposed perforated or grooved cylinders or discs which may be fixed r movable relatively to each other, the arrangement being such as to bring the coni stituents of the mixture into intimate-contact. So far as the methods which are known to me are concerned, the degree of emulsification hitherto attained has not been such as to meet all the requirements of commercial practice. For example, although a relatively stable emulsion could be produced by reconstituting the separated contents of milk, there was lacking the quality of true flavour. I have found as the result of experiment that 3 flavour, amongst other qualities of an emulsion is to a great extent dependent upon the extent to which the constituents of the mixture are split up or divided and brought into intimate contact. I

0 The method therefore according to the present invention is to pass the mixture through a labyrinthine duct with a sequence of abrupt changes of direction andvelocity to bring the constituents into a fine state of subdivision and intimate contact and then to intensify the subdivision and the-turbulence at or near the outlet of the duct to produce a higher degree of emulsification. This is accomplished by throttling the outlet of the 0 duct to the requisite extent, such throttling being preferably adjustable or variable to suit the requirement of different circumstances. v The apparatus employed for carrying out the method may be of the centrifugal or static type but in any case comprises broadly a casing, an inlet in the casing for the mixture to be emulsified, a labyrinthine duct or ducts in the casing confined on all sides, means for forcing the mixture through said duct or ducts, a throttle in the discharge outlet of each duct and a receptacle provided with a de livery spout for collecting and delivering the emulsion.

It should be noted that the ducts employed 55 according to this invent-ion are of such character as to prevent any lateral spreading of the stream between the inlet and discharge orifices, that is to say, they are confined on all sides as will hereinafter transpire.

Further features of the invention will be hereinafter described with reference to the accompanying drawings, in which Figure 1 is a vertical fragmentary section of a centrifugal type of machine.

Figure 2 is. a detail of the drum base, Figure 3 shows the drum base and spindle assembled,

Figure 4 shows the drum ring in plan and in cross-section,

Figures 5 and 6 show details of the drum cover or casing,

Figure 7 is a fragmentary section of a static type of machine, s

Figure 8 is a detail of duct formation, and Figure 9 is a diagrammatic plan of Figure 7.

Referring to Figures 1 to 6 of the accom panying drawings, 1 is the pedestal of a centrifugal type of emulsifier, 2 the driving spindle and 3 the usual type of resilient buffer. The lower part of the machine which is of the usual construction has for the sake of clearness not been shown. Mounted on the spindle 2 is a casing consisting of a hollow sleeve 4: flanged at 5 and pinned to the spindle at 6. Above this hollow sleeve is located an inlet pipe 7 for the mixture to be emulsified. The casing supplies a drum base 8, shown in detail in Figures 2 and 3, and consisting of a ring supported by the flange 5. This ring is rebated at 9 to accommodate the drum cover 10 which is held in position by a sleeve 11 and nut 12. An annular channel 13 is formed in the drum base 8 to receive the drum ring l l shown in detail in Figure 4. The boss 15 of the drum base is provided with channels 16, for example four, com municating with the annular channel 13. A similar number of escape outlets or orifices fits snugly into the annular channel 13 and is recessed on both sides, between alternate pairs of adjacent holes, to form labyrinthine ducts 19 leading from the inner to the outer periphery of the ring. The inlet ends of these ducts communicate with the channels 16 and the outlet ends with the escape orifices or ducts 17. Flutings 20 may with advantage be formed on each face of the drum disc 14 shown in Figure 4. The drum cover 10 fits over the drum base 8 and makes contact with the drum ring 14 located in the channel 13. The flange 21 of the drum cover fits snug ly in the rebate in, the drum base 8 and is held down through the intermediary of the flanged sleeve 11 and nut F lutings 24 may be formed on the interior faces of the drum cover and drum base and the flange 21 is drilled and tapped at four points 25, in the same radii as the channels 16 and ducts 19 and escape orifices 17. These holes are fitted with grub screws, shown in dotted lines in Figure 1, upon which a flat is formed thus leaving a small discharge orifice for the escaping emulsion as will hereinafter transpn-e.

Just above the upper end of the spindle 2 a series of ports 26 are formed in the sleeve 4, see Figures 1 and 3, and these ports allow the incoming mixture to pass into the annnla r space 27 formed between the sleeves 4 and 11 whence it finds its way to the channels 16. To accelerate the mixture, a series of radial vanes or ribs is preferably provided either on the inner periphery of the sleeve 11 or the outer periphery of the sleeve 4. These are indicated at 28 in Figure 6.

The operation of the device thus far described is as follows. The mixture, for example milk powder, hot water and butter in predetermined proportions is admitted at 7 and fills the chamber 29 and passes, through ports 26 into the annular chamber 27 thence into the channels 16 and labyrinthine ducts .19 to the escape orifices 17 and finally through the discharge orifices formed by the flats on the grub screws at 25 in the flange of the drum cover 10. During its passage the fluid is subjected to great turbulence and frequent changes of direction and when passing through the orifices in the flange 17 of the drum base the fluid is subjected to vortex motion in the holes on the median circumference of flange 17 The throttling effect at manner.

the outlets of the duets with the changes of direction and the vortex motion adjacent the discharge orifices greatly enhances the emulsifying effect.

The discharged emulsion is collected in a receptacle 30 formed of sheet metal and attached to the pedestal 1 in the customary discharge spout 31. Another receptacle 32 formed of sheet metal is fitted into the receptacle 30 and this upper receptacle 32 is provided with a centre tube and a cover 34. This receptacle conducts away any surplus of mixture with which the machine cannot cope and such mixture is discharged through a spout 35. The centre tube 33 is provided with a cap 36 which provides a very fine clearance between it and the rotating portion of the machine.

Battles not shown are fitted in the receptacle 30 for the purpose 'of arresting the or bital motion of the discharged emulsion.

Itis important in many cases to aerate the emulsion before it leaves spout 31 such for instance when cream is being manufactured from its constituents or ice cream is being aroduced. Aeration of the emulsion may be accomplished in several ways, for instance, the bafiles within receptacle 30 induce a flow of air down the centre tube 33 which air passes out through spout 31. This flow of air can be controlled in various ways for regulating the aeration of the emulsion, for instance, the amount of clearance between cap 36 and the rotating parts of the machine may be varied to control the flow of air. Alternatively, the spout 35 of the overflow receptacle 32 may be fitted with a hinge flap 37 which does not fit too tightly and while permitting of overflow mixture to be discharged, limits the amount of air which can gain access to the interior of the overflow vessel and therefore to the centre tube 33. The amount of air thus admitted to the overflow receptacle may be regulated by the screw 38 which regulates the amount of closing of the flap 37 As an alternative arrangement, the spout 35 may discharge into a container which forms a fluid seal so that air cannot find its way into the overflow receptacle by way of spout 35. In this case an air tube 39 may be introduced through the cover 34 and extended through the centre tubes 33 and provided v at its outer extremity with a regulating valve 01' cock 40. In this way the amount of air admitted to the centre tube 33 and to the receptacle 30 can be regulated.

For the purpose of adjusting the rate of flow or discharge of the emulsion the grub screws in the flange 21 may be changed that is to say, sets of grub screws with dill'erent sizes of flats formed thereon may be used to vary the size of the discharge orifices in flange 21.

The receptacle is provided with a the hollow sleeve 4 able for use in the centrifugal or static forms of constructions. In this modification, thehaving flats thereon as to those acquainted with the art..-

casing .41 maybe mounted on the spindle 2 ina convenient manner and this casinghas a lower drum portion t2 '1nto which are screwed a series of radial tubes 4, for example four as shown in Figure These tubes contain cylindrical plugs 44 which are drilled with aseries of holes 45 and recessed between adjacent pairs of holes on opposite sides to form labyrinthine ducts as described above in connection with the drum ring 14. Near the discharge-ends of each'of these ducts a hole 46' is-drilled and this hole communi cates with the adjacent holes by meansof a slit and-with the extremity of the plug by meansof another slit, these slits constituting the discharge orifices. It is in the space formed by the holes 46 that vortex motion of the fluid takes place. The ends of the tubes aredrilled and fitted with grub screws 47 hereinbefore described whereby the emulsion discharged from the labyrinthine ducts in the plugs 44 escapes. A detail of the plug in'cro'ss-sec- Lion is'shown in Figure 8. I

" The. arrangement of Figirres 7, 8 and 9 may be used as ,a-static form by simply connectin the sleeve of the casing 41 to a supply ,va ve in a manner which it .will be clear A The air entering the emulsifier may be in'-- exclude dust particles a-fsuitable filterto andalso through asterilizing agent. Ozoneor some other gascons or. vapour'izedagjent-m'ay be injected mto .duced to pass through the air stream and passed out throughthe emulsion discharge spout into the cooler casing,andthen discharged to atmosphere; Al-

ternativ ely the air in the emulsion andoverflowreceptacles ma be sterilized and-caused to circulate in a c osed circuit. As stated above suitable gas or vapour with or withoutairmay be mixed withthe emulsion. Q

' 1. A device for emulsifying a'mixture comprising a casing, an inlet in the casing, a labyrinthine duct in said casing confined on; all sides, means for forcing the mixture through said duct, there being a discharge orifice at the end of theduct, sa1d orifice having a smaller cross-sectional area than the duct. n a

-2. A device for emulsifying a mixture comprising a casing having an inlet, a laby- 'motion of the disc receptacle arranged to receive liquid over-' for rotating said .a receptacle to receive the -mixture.

rinthine duct in said casing confined on all sides, -means for forcing the mixture through said duct, there being a constricted discharge opening at the end of the duct, and a receptacle adapted to receive the emulsified mixture from said discharge .opening. 1

' 3. A device, for. emulsifying a mixture comprising a spindle, means for rotatingsaid spindle, a drum mounted on said spindle, a

radial labyrinthine duct in said drum, said duct being confined on'all sidesfa constricteddischarge orifice at the outlet end of the duct,

and a receptacle to receive-the mixture dis charged through said orifice.

4. A centrifugal apparatus ing a mixture comprising a spindle, means for rotating said spindle, a radial labyrinthine duct in said drum said duct being" confined on all sides, a constricted discharge opening at the'outlet end of the duct, aresaid receptacle adapted to arrest the orbital flowing from the intake o f'said duct. g

6, A centrifugal apparatus for emulsify ijng a'mi-xture comprising aspindle, means spindle, a. radial labyrinthine duct in-said drum said 'duct being 'confined on all s'ides,;a constricted-discharge openingat the tacle to, receive the .mixture' discharged for emulsify- I pening at the outlet end of the duct, 'a reep-',

opening, vanes 1n outlet end of the duct, a recep- 'lti arged emulsion, ,and'a I through said discharge opening,.vanes 1n to arrest the orbital said receptacle adapted emulsion, and

motion of the discharged 'means'to control the amount of air admitted to said receptacle.

prising a spindle, means for rotating said spindle, radial labyrinthine duct in. said drum, sa d duct being "confined on all sides, a constricted discharge orifice at the outletend of the dudlct,

7. A device for emulsifying a mixture coma drum mounted on-said spindle, a

ranged on said drum adapted to induce a flow ofair duringfrotation of the drum.

8. A device for emulsifying a mixture.

comprising). casing, an inlet in the casing, a labyrinthine duct 1n said casing confined on allsides, meansfor forcing the 'mixture through'said duct, 'there be ng a' .'dis c'harge' duct, said orifice havorifice at the end of the I I ing a smaller cross-sectional area thanthe duct, and means whereby the size of the discharge orifice may be regulated.

9. A device for emulsifying a mixture comprising a casing, an inlet in the casing, a labyrinthineduct in said casing confined on all sides, means for forcing the mixture through said duct, there being, a discharge orifice at the end of the duct, said discharge orifice comprising two slits of smaller crosssectional area than the duct and opening into an enlarged space.

10. A device for emulsifyin'ga mixture comprising a casing, an inlet in the casing, a labyrinthine duct in said casing confined on all sides, means for forcing the mixture through said duct, there being a discharge orifice at theend of the duct, said orifice having a smaller cross-sectional area than the duct, andrmeans arranged adjacent said discharge orifice for producing a vortex in the mixture as it is forced throu h the duct.

ALFRED WALKL R EMPSON. 

